昆虫学报 ›› 2019, Vol. 62 ›› Issue (5): 624-633.doi: 10.16380/j.kcxb.2019.05.011

• 研究论文 • 上一篇    下一篇

中国小菜蛾群体遗传变异的时空动态

柯富士1,2,3, 尤士骏1,2,3, 黄素梅1,2,3, 刘天生1,2,3, 谢丹丹1,2,3, 尤民生1,2,3,*   

  1. (1. 福建农林大学, 闽台作物有害生物生态防控国家重点实验室, 福州 350002; 2. 福建农林大学应用生态研究所, 福州 350002; 3. 福建农林大学, 教育部害虫生态防控国际合作联合实验室, 福州 350002)
  • 出版日期:2019-05-20 发布日期:2019-05-16

Spatiotemporal dynamics of genetic variation in populations of the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae), in China

KE Fu-Shi1,2,3, YOU Shi-Jun1,2,3, HUANG Su-Mei1,2,3, LIU Tian-Sheng1,2,3, XIE Dan-Dan1,2,3, YOU Min-Sheng1,2,3,*    

  1.  (1. State Key Laboratory for Ecological Pest Control of Fujian/Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China; 2. Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou 350002, China; 3. Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China)
  • Online:2019-05-20 Published:2019-05-16

摘要:

【目的】小菜蛾Plutella xylostella是十字花科蔬菜最重要的迁移性害虫之一,在中国越冬区(OR)的群体和季节性繁殖区(SBR)的群体之间具有“源汇”关系和复合群体的特征。本研究旨在揭示中国小菜蛾群体遗传变异的时空动态,以期进一步阐明该虫的迁移特性及其对区域灾变的影响。【方法】基于已经发表的4组不同采样时间中国小菜蛾COI序列(共1 567条)数据,将每个数据集细分为3组:OR群体、SBR群体以及特定采样时间(ST)的群体。对不同组(群体)进行遗传多样性、遗传分化、单倍型相似性和群体演化史的分析。【结果】基于COI序列的小菜蛾群体遗传变异分析结果表明,同一采样时间内,OR群体和SBR群体遗传多样性水平相当。虽然SBR群体在单倍型频率上不稳定,导致包含SBR的群体间遗传分化较大,但SBR群体单倍型均能够在同一采样时间的OR群体中找到,或SBR单倍型仅与OR单倍型相差2个碱基以内;SBR群体中单倍型频率在不同年份间变化大,遗传分化最大,而ST群体之间遗传分化的变异水平最低。不同采样时间样品COI序列的碱基错配分布图呈现相同的单峰状,且不同采样时间样本主要是由几种相同的单倍型构成。【结论】这些结果表明:迁移是影响中国季节性繁殖区小菜蛾群体遗传变异的主要因素;中国不同区域的小菜蛾群体遗传变异在时间尺度上具有稳定性和相关性。小菜蛾复合群体特征为阐明其季节性迁移特性提供了重要的生态学依据。

关键词:  小菜蛾, 时空尺度, 遗传变异, 迁移, 越冬区; 季节性繁殖区

Abstract:  【Aim】 The diamondback moth, Plutella xylostella L., is one of the most important dispersal pests of cruciferous vegetables worldwide, and it is featured by the interrelated metapopulations of “source-sink” between overwintering regions (OR) and seasonally breeding regions (SBR) in China. This study aims to investigate the spatiotemporal dynamics of genetic variation in P. xylostella populations in China and to further uncover the effect of dispersal behavior on its regional outbreaks. 【Methods】 The genetic variation of P. xylostella populations was investigated based on four independent datasets of 1 567 COI sequences of P. xylostella at different sampling time in China. Each dataset was classified into three groups, i.e., OR populations, SBR populations and populations sampled at a given sampling time (ST). The genetic diversity, genetic differentiation, haplotype similarity and demography history of these populations were investigated. 【Results】 Genetic variation analysis of P. xylostella populations based on COI sequences revealed a comparable genetic variation between OR and SBR populations sampled at the same time. Although the unstable haplotype frequency in SBR led to a great genetic differentiation of SBR-involved populations, COI haplotypes in SBR populations either could be found in OR populations sampled at the same time or showed a limited difference (<2 bp) from the COI haplotypes in OR populations. The haplotype frequency of SBR populations varied greatly among different years. Variation of genetic differentiation between SBR populations was the highest in all population combinations, while that between ST populations was the lowest. Haplotype analysis at different sampling time showed a similar pattern in nucleotide mismatch distributions, and the similar haplotype pattern consists of several dominant haplotypes. 【Conclusion】 Our results indicate that dispersal is the major factor in shaping the genetic variation of SBR populations of P. xylostlla, and P. xylostella populations tend to exhibit a temporal stability and interrelation of genetic variation in different regions of China. The nature of metapopulation provides an important ecological base for understanding the seasonal dispersal of P. xylostella.

Key words: Plutella xylostella, spatiotemporal scale, genetic variation, dispersal, overwintering region, seasonally breeding region